2007-05-21 21:31:10 · 7 answers · asked by Roxy 1 in Science & Mathematics ➔ Astronomy & Space
Gravity, my friend. Gravity.
Mars is much smaller than Earth, so there is less gravity. Also, unlike Earth, Mars doesn't have tectonic plates that shift, so rather than a volcano creating a chain of islands like Hawaii, it just all piles up in the same spot. :)
Hope this helps.
2007-05-21 21:35:53 · answer #1 · answered by Meirelle 2 · 2⤊ 0⤋
Plate tectonics.
On Earth, the crust is divided into plates that move, sliding under one another, pulling away from one another, bunching up against each other to form mountain ranges. It is this movement that keeps our volcanoes from getting as large as the ones on Mars.
Take Hawaii as an example. It is a chain of volcanoes, but only one is active. The others all, at one time, occupied the place now held by the active volcano. They sat above a 'hot spot' in the mantle which broke through the crust causing a volcano. As the plates of the Earth's crust moved, the volcano was carried away from the hot spot, and the next burst of activity broke through the crust in a new location. The original volcano became extinct, no longer supplied from below. And so the process continued until a long chain of extinct volcanoes formed, with an active one at the head of the chain, sitting over the hot spot that fuelled the one at the tail of the chain.
On Mars there are no plate tectonics. A volcano will sit over the same spot for millions of years, and each subsequent eruption will add to it until it becomes far larger than anything on Earth. Because it is never carried away from the hot spot, it will grow and grow and grow.
2007-05-22 05:08:08 · answer #2 · answered by Jason T 7 · 1⤊ 1⤋
jason is pretty much right, but he also forgot one thing. on earth the crust is thinner than it is on mars. earthly volcanoes sink into the crust slightly. this is true of hawaii. on mars the volcanoes don't sink and so they end up being higher.
also there isn't as much erosion so the volcanoes last longer. and the plate tectonic thing is right to. the volcanoes never move so they continue to grow and grow. and the gravity thing is wrong. mars does have less gravity but that doesn't help its volcanoes any.
2007-05-22 06:35:04 · answer #3 · answered by Tim C 5 · 0⤊ 1⤋
The tectonic arguments in this thread are mostly wrong.
The sliding of plates is not what limits the heights of mountains: gravity does. Given the known elasticity of rock as a function of pressure, it is in fact possible to calculate the maximum height of a mountain on a planet. And guess what: on Earth that height is about 9 km (the height of Everest, more or less), and on Mars (whose gravity is about a third of Earth) it is about three times that -- namely the height of Olympus Mons, the tallest Martian peak.
2007-05-22 14:37:13 · answer #4 · answered by Astronomer1980 3 · 0⤊ 1⤋
Wait... There's one super volcano in the island of Sumatra, Indonesia. It's very big! Now, it's extinct, forming a deep lake large enough to be spotted from outer space. I think I saw it in discovery or national geographic channel.
2007-05-22 04:51:37 · answer #5 · answered by MasterOfAsking 1 · 0⤊ 1⤋
Because we would be obliterated with the volcanoes of Mars on Earth.
2007-05-22 04:34:34 · answer #6 · answered by DAVID C 3 · 0⤊ 3⤋
because they are. JK! LOL! If you're not sure, check out NASA's webpage, it'll tell ya! Hope I've helped!!!
2007-05-25 21:03:45 · answer #7 · answered by Thomas 3 · 0⤊ 0⤋